1. Field of the Invention
The present invention relates to a vibration-isolating device for a steering wheel of a traveling working vehicle equipped with a wheel steering mechanism.
2. Description of the Related Art
A device disclosed in JP 2007-237786A (paragraph [0023], FIGS. 2 to 4) in which a steering post is supported on the top surface of a transmission case via rubber vibration isolators, and a steering shaft connected to a steering wheel is supported within the steering post, is known as a steering wheel vibration-isolating device of a working vehicle of this type.
In this conventional device, only the steering post supported on the transmission case is supported in a vibration-isolating manner, so that vibration transmitted from a wheel steering mechanism to the steering wheel through the steering shaft cannot be blocked, and there is a problem in that vibration of the steering wheel cannot be suppressed.
Moreover, a structure disclosed in JP 8-207784A, in which a steering shaft connected to a steering wheel is supported within a steering post via a cylindrical rubber provided in an upper portion of the steering post and upper and lower rubber bushes holding a bearing inside thereof, is known as a structure for supporting a steering shaft.
Also in this conventional structure, the steering shaft is supported in a vibration-isolating manner only with respect to the steering post, so that vibration transmitted from a wheel steering mechanism to the steering wheel through the steering shaft cannot be blocked, and so there is the problem in that vibration of the steering wheel cannot be suppressed.